A pheochromocytoma (fee-o-kroe-moe-sy-TOE-muh) is a rare, usually noncancerous (benign) tumor that develops in an adrenal gland. You have two adrenal glands —one located at the top of each kidney. Usually, a pheochromocytoma develops in only one adrenal gland. But tumors can develop in both.

If you have a pheochromocytoma, the tumor releases hormones that may cause high blood pressure, headache, sweating and symptoms of a panic attack. If a pheochromocytoma isn't treated, severe or life-threatening damage to other body systems can result.

Most pheochromocytomas are discovered in people between the ages of 20 and 50. But the tumor can develop at any age. Surgery to remove a pheochromocytoma usually returns blood pressure to normal.

Signs and symptoms of pheochromocytomas often include:

• High blood pressure
• Headache
• Heavy sweating
• Rapid heartbeat
• Tremors
• Paleness in the face
• Shortness of breath
• Panic attack-type symptoms

Less common signs or symptoms may include:

• Anxiety or sense of doom
• Constipation
• Weight loss

Symptomatic spells

The symptoms listed above may be constant, or they may occur, or get stronger, occasionally. Certain activities or conditions can make symptoms worse, such as:

• Physical exertion
• Anxiety or stress
• Changes in body position
• Labor and delivery
• Surgery and anesthesia

Foods high in tyramine, a substance that affects blood pressure, also can make symptoms worse. Tyramine is common in foods that are fermented, aged, pickled, cured, overripe or spoiled. These foods include:

• Some cheeses
• Some beers and wines
• Chocolate
• Dried or smoked meats

Certain medications that can make symptoms worse include:

• Monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil), tranylcypromine (Parnate) and isocarboxazid (Marplan)
• Stimulants, such as amphetamines or cocaine

When to see a doctor

Although high blood pressure is a primary sign of a pheochromocytoma, most people who have high blood pressure don't have an adrenal tumor. Talk to your doctor if any of the following factors are applicable to you:

• Difficulty controlling high blood pressure with current treatment
• Episodic worsening of high blood pressure
• A family history of pheochromocytoma
• A family history of a related genetic disorder: multiple endocrine neoplasia, type 2 (MEN 2); von Hippel-Lindau disease; familial paraganglioma or neurofibromatosis 1 (NF1)

Researchers don't know exactly what causes a pheochromocytoma. The tumor develops in specialized cells, called chromaffin cells, located in the center of an adrenal gland. These cells release certain hormones, primarily adrenaline (epinephrine) and noradrenaline (norepinephrine), that help control many body functions, such as heart rate, blood pressure and blood sugar.

The role of hormones

Adrenaline and noradrenaline trigger your body's fight-or-flight response to a perceived threat. The hormones cause your blood pressure to increase and your heart to beat faster. They prepare other body systems that enable you to react quickly. A pheochromocytoma causes more of these hormones to be released and causes them to be released when you're not in a threatening situation.

Related tumors

While most of the chromaffin cells are located in the adrenal glands, small clusters of these cells are also in the heart, head, neck, bladder, back wall of the abdomen and along the spine. Chromaffin cell tumors, called paragangliomas, may result in the same effects on the body.

People who have certain rare inherited disorders have an increased risk of pheochromocytoma or paraganglioma. Tumors associated with these disorders are more likely to be cancerous. These genetic conditions include:

• Multiple endocrine neoplasia, type 2 (MEN 2) is a disorder that results in tumors in more than one part of the body's hormone-producing (endocrine) system. Other tumors associated with this condition can appear on the thyroid, parathyroid, lips, tongue and gastrointestinal tract.
• Von Hippel-Lindau disease can result in tumors at multiple sites, including the central nervous system, endocrine system, pancreas and kidneys.
• Neurofibromatosis 1 (NF1) results in multiple tumors in the skin (neurofibromas), pigmented skin spots and tumors of the optic nerve.
• Hereditary paraganglioma syndromes are inherited disorders that result in either pheochromocytomas or paragangliomas.

High blood pressure can damage multiple organs, particularly tissues of the cardiovascular system, brain and kidneys. This damage can cause a number of critical conditions, including:

• Heart disease
• Stroke
• Kidney failure
• Problems with the nerves of the eye

Cancerous tumors

Rarely, a pheochromocytoma is cancerous (malignant), and the cancerous cells spread to other parts of the body. Cancerous cells from a pheochromocytoma or paraganglioma most often travel to the lymph system, bones, liver or lungs.

Your doctor might order several tests.

Lab tests

The following tests measure levels of adrenaline, noradrenaline or byproducts of those hormones in your body:

• 24-hour urine test. In this test, you collect a urine sample every time you urinate during a 24-hour period. Ask for written instructions about how to store, label and return the samples.
• Blood test. Your doctor draws blood to be tested in the lab.

For both types of tests, talk with your doctor about special preparations, such as fasting or skipping a medication. Don't skip a medication dose without instructions from your doctor.

Imaging tests

If the lab test results suggest the presence of a pheochromocytoma or paraganglioma, your doctor will likely order one or more imaging tests to locate a possible tumor. These tests may include:

• CT scan, a specialized X-ray technology
• MRI, which uses radio waves and a magnetic field to produce detailed images
• M-iodobenzylguanidine (MIBG) imaging, a scanning technology that can detect tiny amounts of an injected radioactive compound taken up by pheochromocytomas or paragangliomas
• Positron emission tomography (PET), a scanning technology that also can detect radioactive compounds taken up by a tumor

Imaging studies done for other reasons

A tumor in an adrenal gland might be found during imaging studies done for other reasons. In such cases, your doctor will generally order additional tests to determine the nature of the tumor.

Genetic testing

Your doctor might recommend genetic tests to determine whether a pheochromocytoma is related to an inherited disorder. Information about possible genetic factors can be important for many reasons:

• Because some inherited disorders can cause multiple conditions, test results may indicate the need to screen for other medical problems.
• Because some disorders are more likely to be recurrent or cancerous, your test results may affect treatment decisions or long-term plans to monitor your health.
• Results from your tests may suggest that other family members should be screened for pheochromocytoma or related conditions.

Ask your doctor about genetic counseling services that can help you understand the benefits and implications of genetic testing.

The primary treatment for a pheochromocytoma is surgery to remove the tumor. Before you have surgery, your doctor will likely prescribe specific blood pressure medications that block the actions of the high-adrenaline hormones to lower the risk of developing dangerously high blood pressure during surgery.

Preoperative preparations

You'll likely take two drugs for seven to 10 days that help lower blood pressure before surgery. These drugs will either replace or be added to other blood pressure drugs you take.

• Alpha blockers. These drugs keep smaller arteries and veins open and relaxed, improving blood flow and decreasing blood pressure. Alpha blockers include phenoxybenzamine, doxazosin (Cardura) and prazosin (Minipress). Side effects might include irregular heartbeat, dizziness, fatigue, vision problems, sexual dysfunction in men and swelling in the limbs.

• Beta blockers. These drugs cause your heart to beat more slowly and with less force. They also help keep blood vessels open and relaxed. In your surgery preparation, your doctor will likely prescribe a beta blocker several days after starting the alpha blocker.

  Beta blockers include atenolol (Tenormin), metoprolol (Lopressor, Toprol-XL) and propranolol (Inderal, Innopran XL). Possible side effects include fatigue, upset stomach, headache, dizziness, constipation, diarrhea, irregular heartbeat, difficulty breathing and swelling in the limbs.

• High-salt diet. Alpha and beta blockers widen the blood vessels, causing the amount of fluid within the blood vessels to be low. This can cause dangerous drops in blood pressure with standing. A high-salt diet will draw more fluid inside the blood vessels, preventing the development of low blood pressure during and after surgery.

Surgery

In most cases, your surgeon removes the entire adrenal gland with a pheochromocytoma with minimally invasive surgery. Your surgeon will make a few small openings through which he or she inserts wandlike devices equipped with video cameras and small tools.

The remaining healthy adrenal gland carries out the functions normally performed by two. Blood pressure usually returns to normal.

In some cases, such as when the other adrenal gland has been removed, your doctor might remove only the tumor, sparing some healthy tissue.

If a tumor is cancerous, the tumor and other cancerous tissue will be removed. However, even if all of the cancerous tissue isn't removed, surgery might limit hormone production and provide some blood pressure control.

Cancer treatments

Very few pheochromocytomas are cancerous. As such, research about the best treatments is limited. Treatments for cancerous tumors and cancer that has spread in the body, related to a pheochromocytoma, include:

• MIBG. This radiation therapy combines MIBG, a compound that attaches to adrenal tumors, with a type of radioactive iodine. The treatment goal is to deliver radiation therapy to a specific site and kill cancerous cells.
• Peptide receptor radionuclide therapy (PRRT). PRRT combines a drug that targets cancer cells with a small amount of a radioactive substance. It allows radiation to be delivered directly to the cancer cells. One PRRT drug, lutetium Lu 177 dotatate (Lutathera), is used to treat advanced neuroendocrine tumors.
• Chemotherapy. Chemotherapy is the use of powerful drugs that kill fast-growing cancer cells.
• Radiation therapy. This may be used for symptomatic treatment of tumors that have spread to the bone, for example, that are causing pain.
• Targeted cancer therapies. These medications hinder the function of naturally occurring molecules that promote the growth and spread of cancerous cells.

You're likely to start by seeing your primary care doctor. Then you might be referred to a doctor who specializes in hormonal disorders (endocrinologist).

Here's some information to help you get ready for your appointment.

What you can do

When you make the appointment, ask if there's anything you need to do in advance, such as fasting before having a specific test. Make a list of:

• Your symptoms, including any changes from normal, when they began and how long they last
• Key personal information, including major stresses, recent life changes and family medical history
• All medications, vitamins and other supplements you take, including doses
• Questions to ask your doctor

Take a family member or friend along, if possible, to help you remember the information you get.

For a pheochromocytoma, questions to ask your doctor include:

• What's likely causing my symptoms?
• Other than the most likely cause, what are other possible causes for my symptoms?
• What tests do I need?
• Is my condition likely temporary or chronic?
• What's the best course of action?
• What are the alternatives to the primary approach you're suggesting?
• I have other health conditions. How can I best manage them together?
• Are there restrictions I need to follow?
• Should I see a specialist?
• Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions.

What to expect from your doctor

Your doctor is likely to ask you questions, including:

• Have your symptoms been continuous or intermittent?
• Does anything seem to improve your symptoms?
• What, if anything, appears to bring on or worsen your symptoms?
• Have you been diagnosed with other medical conditions? If so, what treatment are you getting?
• Is there a family history of adrenal or other endocrine tumors?